When you see "4.0.30319.0" in a file property or system log, it signifies that the system is running the original release of .NET Framework 4.0. This specific string became ubiquitous because .NET 4.0 was installed by default on Windows 7 (via Windows Update) and was integral to Windows 8 and Windows 10. Even today, many modern applications targeting .NET Framework 4.8 will still load CLR version 4.0.30319 (or a variation of it) because the underlying runtime engine was incrementally upgraded rather than replaced entirely.
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() [CLR Version 4.0.30319.0] Microsoft Common Language Runtime Version 4.0.30319.0.l
Because this CLR version is so pervasive, misconfigurations often lead to specific errors. When you see "4
While 4.0.30319.0 is the common reported string, the actual runtime version may be higher. Here is how to get the truth: at System
You have an assembly compiled with an older CLR (2.0) trying to load into CLR 4.0 without proper configuration.